diff --git a/Makefile b/Makefile
index dba21f545..ac39ea5aa 100644
--- a/Makefile
+++ b/Makefile
@@ -3,8 +3,8 @@
 # Needs to have oneof support: Ubuntu vivid's is too old :(
 PROTOCC:=protoc-c
 
-# Alpha has checksequenceverify, segregated witness+input-amount-in-sig+confidentual-transactions, schnorr
-FEATURES := -DHAS_CSV=1 -DALPHA_TXSTYLE=1 -DUSE_SCHNORR=1
+# Alpha has checksequenceverify, segregated witness+input-amount-in-sig+confidentual-transactions, schnorr, checklocktimeverify
+FEATURES := -DHAS_CSV=1 -DALPHA_TXSTYLE=1 -DUSE_SCHNORR=1 -DHAS_CLTV=1
 # Bitcoin uses DER for signatures
 #FEATURES := -DSCRIPTS_USE_DER
 
diff --git a/bitcoin/script.c b/bitcoin/script.c
index 03cb07606..cc6c3b779 100644
--- a/bitcoin/script.c
+++ b/bitcoin/script.c
@@ -33,6 +33,14 @@
 /* OP_NOP, otherwise bitcoind complains */
 #define OP_CHECKSEQUENCEVERIFY	0x61
 #endif
+
+#ifdef HAS_CLTV
+#define OP_CHECKLOCKTIMEVERIFY	0xB1
+#else
+/* OP_NOP, otherwise bitcoind complains */
+#define OP_CHECKLOCKTIMEVERIFY	0x61
+#endif
+
 static void add(u8 **scriptp, const void *mem, size_t len)
 {
 	size_t oldlen = tal_count(*scriptp);